JP5887824B2 - Polyester film for molding - Google Patents

Description

  The present invention relates to a polyester film for molding which is excellent in moldability, dimensional stability and processability and has a good appearance after molding.

  In recent years, in the field of automotive parts, electronic equipment, and building materials, there has been an increasing demand for environmentally-friendly loads such as solvent-less coating and hexavalent chromium substitution, and the introduction of film decoration methods for molded parts using molded decorative films has progressed. Yes. Examples of the film decorating method include a simultaneous molding transfer method called an in-mold transfer method, a vacuum (pressure air) molding method, and an insert molding method. In any construction method, the moldability of the film is an important factor, and a film for molding transfer foil (Patent Document 1) or a sheet for vacuum molding (Patent Document 2) using an unstretched film with high moldability is proposed. Has been. While an unstretched film is excellent in moldability, it is inferior to a biaxially oriented film in processability because it has low heat resistance and chemical resistance. As the biaxially stretched film for molding, the composition and melting point of each layer of the biaxially stretched polyester film (Patent Document 3) that defines the elongation of the film, the ratio of the elongation in the longitudinal direction and the transverse direction, etc. A laminated polyester film for molding within a certain range (Patent Document 4) has been proposed.

  Conventionally, biaxially oriented films have been used to mold relatively shallow shapes, but there is an increasing need for biaxially oriented films that can be molded even in deeper shapes, improving moldability without compromising workability. There is a need for biaxially oriented films.

JP 2009-39860 A JP 2010-99901 A JP 2009-292949 A JP 2010-208341 A

  An object of the present invention is to provide a polyester film for molding that is excellent in moldability, dimensional stability and processability, and has a good appearance after molding. .

That is, the present invention has the following features.
(1) The MOR-c value is 1.81 to 8.0, the F100 value at 150 ° C. in the direction orthogonal to the orientation angle is 5 MPa to 60 MPa , the load is 19.6 mN, and from 25 ° C. to 220 ° C. the polyester film for thermal dimensional change of from 0 + Ru 3% der cast films at 180 ° C. in the orientation angle direction when the temperature was raised at a heating rate 5 ° C. / min.
( 2 ) The molding polyester film according to (1) , comprising a three-layer constitution of B layer / A layer / B layer.
( 3 ) 95 mol% or more of the dicarboxylic acid component of the polyester constituting the A layer is terephthalic acid, 60 to 95 mol% of the glycol component is ethylene glycol, 5 to 40 mol% is 1,4-cyclohexanedimethanol, One or more glycols selected from the group consisting of 2,2-dimethyl-1,3-propanediol and 1,4-butanediol, and 95 mol% or more of the dicarboxylic acid component of the polyester constituting the B layer Among terephthalic acid and glycol components, 80 mol% or more is ethylene glycol, and 0 to 20 mol% is composed of 1,4-cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol and 1,4-butanediol. The molding polyester fill according to ( 2 ), which is at least one glycol selected from the group Mu.
( 4 ) Of the dicarboxylic acid component of the polyester constituting the A layer, 95 mol% or more is terephthalic acid, and among the glycol components, 80 to 95 mol% is ethylene glycol, 5 to 20 mol% is 1,4-cyclohexanedimethanol and And / or 2,2-dimethyl-1,3-propanediol, 95 mol% or more of the dicarboxylic acid component of the polyester constituting the B layer is terephthalic acid, 90 mol% or more of the glycol component is ethylene glycol, 0 The molding polyester film according to ( 2 ), wherein 10 mol% is 1,4-cyclohexanedimethanol and / or 2,2-dimethyl-1,3-propanediol.

  According to the present invention, it is possible to obtain a molding polyester film which is excellent in moldability, dimensional stability and processability and has a good appearance after molding.

  Hereinafter, the present invention will be described in detail.

  The inventors of the present invention have found the present invention by intensively studying conditions suitable for the composition, configuration, and production method of the polyester constituting the molding polyester film.

The molding polyester film of the present invention needs to have a MOR-c value of 1.81 to 8.0. More preferably, it is 2.0-7.0, More preferably, it is 2.5-6.0. The MOR value is the ratio (maximum value / minimum value) of the maximum value and the minimum value of the transmission microwave intensity measured by the microwave transmission type molecular orientation meter. The MOR-c value is based on the MOR value. It is converted into a thickness. The MOR-c value in the present invention is converted to 188 μm by the following formula (1).
MOR−c value = (MOR value−1) × tc / t + 1 (1)
Here, t is the thickness of the sample (μm), tc is the reference thickness to be corrected (188 μm), MOR is the ratio of the major axis to the minor axis of the polar coordinate (orientation pattern) obtained by the above measurement, MOR-c The value indicates the MOR value after correction.

  When the MOR-c value is 1.81 to 8.0, the molecular orientation can be moderately biased. The tensile strength in the orientation direction of the molecule is increased, but it can be stretched with low stress in the direction perpendicular to the orientation direction. Since it becomes easy to mold in a direction where the molding stress is low, the film can be more effectively molded depending on the shape of the molded body. Further, since the dimensional change due to heat is suppressed in the direction of high orientation, shrinkage during printing can be suppressed. When the MOR-c value is smaller than 1.81, the molding stress may increase in any direction and the heat shrinkage rate may increase, which is not preferable. When the MOR-c value is larger than 8.0, the orientation in a specific direction is too high, and the moldability may be deteriorated or wrinkles may occur.

  In the molding polyester film of the present invention, the F100 value at 150 ° C. in the direction perpendicular to the orientation angle needs to be 5 MPa or more and 60 MPa or less. The orientation angle is an orientation in which molecules are most polarized in the plane. Similar to the MOR value, the inclination in the orthogonal coordinate system of the major axis of polar coordinates (orientation pattern) measured by a microwave transmission type molecular orientation meter is the orientation angle. More preferably, the F100 value is 10 MPa or more and 50 MPa or less, and further preferably 15 MPa or more and 45 MPa or less. By setting the F100 value within the above range, when the F100 value is smaller than 5 MPa, the film may sag or print when the film is heated for decorative molding, which is not preferable. When the F100 value is larger than 60 MPa, the moldability is lowered, which is not preferable. Here, the F100 value means that a sample cut into a rectangular shape having a test length of 50 mm is preheated for 60 seconds in a thermostat set at 150 ° C., and then a tensile test is performed at a strain rate of 300 mm / min in the direction perpendicular to the orientation angle. It is the stress at the time of 100% elongation. In the present invention, a tensile test was performed in the direction along the orientation angle obtained when measuring the MOR value and in the direction perpendicular to the orientation angle. The elongation in the orientation angle direction becomes the elongation in the molecular chain direction, and the stress increases. Elongation in the direction perpendicular to the orientation angle reduces stress. The F100 value in the orientation angle direction is preferably (F100 value in the direction perpendicular to the orientation angle) or more and 100 MPa or less, more preferably 80 MPa or less, and still more preferably 60 MPa or less. If the F100 value in the orientation angle direction is larger than 100 MPa, the moldability may be insufficient, which is not preferable.

  As a preferred means for setting the MOR-c value and the F100 value at 150 ° C. in the direction perpendicular to the orientation angle within the above range, the molding polyester film is a biaxially oriented film under the conditions described below. It is possible to form a film. The biaxially oriented film is obtained by stretching an unstretched film in the longitudinal direction and then stretching in the width direction, or by stretching in the width direction and then stretching in the longitudinal direction, or by the longitudinal direction of the film. It can be obtained by stretching by a simultaneous biaxial stretching method in which the width direction is stretched almost simultaneously.

  The molding polyester film of the present invention is preferably a biaxially oriented film from the viewpoints of heat resistance and dimensional stability, but the stretching method may be either simultaneous biaxial stretching or sequential biaxial stretching. Among these systems, the tenter system is preferable in terms of film quality.

  The stretching ratio of the biaxial stretching is 3.0 to 4.2 times, preferably 3.0 to 4.0 times, more preferably 3.2 to 3.8 in the longitudinal direction and the width direction. Is double. In this case, either of the stretching ratios in the longitudinal direction and the width direction may be increased or the same. In order to make the MOR-c value 1.81 to 8.0, it is preferable to increase the draw ratio in either the longitudinal direction or the width direction.

  The stretching speed is preferably 1,000% / min to 200,000% / min. More preferably, it is 1,500% / min to 50,000% / min, and more preferably 2,000% / min to 30,000% / min. If the stretching speed is lower than 1,000% / min, productivity may be deteriorated, which is not preferable. On the other hand, when the stretching speed is higher than 200,000% / min, it is difficult to control the orientation, which is not preferable.

  In the case of the sequential biaxial stretching method of stretching in the longitudinal direction after stretching in the longitudinal direction, the MOR-c value is set to 1.81 to 8 by increasing the stretching ratio in either the longitudinal direction or the width direction. 0.0, which is preferable. In that case, it is preferable to increase the draw ratio in the width direction. If the longitudinal direction is increased, it may be difficult to control the orientation. The stretching conditions with the MOR-c value in the above range include, for example, a stretching ratio in the longitudinal direction of 3.0 to 4.2 times and a stretching ratio in the width direction of 3.0 to 4.2 times, preferably the longitudinal direction. The stretching ratio in the direction is 3.0 to 3.8 times, the stretching ratio in the width direction is 3.2 to 4.0 times, and the difference in the stretching ratio is 0.1 or more and 0.8 or less, more preferably 0.8. It is preferable to set it to 2 or more and 0.5 or less. It is preferable that the difference Δn in refractive index between the longitudinal direction and the width direction of the biaxially oriented film is 0.005 or more and 0.04 or less. More preferably, it is 0.01 or more and 0.035 or less. It is preferable for Δn to be in the above range since the MOR-c value can be easily set in a preferable range. If Δn is smaller than 0.005, the MOR-c value tends to be lower than the preferred range, and if Δn is larger than 0.04, the MOR-c value tends to be larger than the preferred range.

  The preheating temperature for stretching in the longitudinal direction is preferably 80 to 100 ° C, more preferably 85 to 95 ° C. The stretching temperature in the longitudinal direction is preferably from 80 ° C. to 110 ° C., more preferably from 85 ° C. to 100 ° C., and most preferably from 85 ° C. to 95 ° C. The uniaxially stretched film after stretching in the longitudinal direction preferably has an Δn of 0.01 or more and 0.05 or less. More preferably, it is 0.015 or more and 0.04 or less. When Δn is in the above range, the orientation of the uniaxially stretched film is in an appropriate range, and the orientation in the width direction is easily set in the appropriate range during stretching in the width direction. When Δn is larger than 0.05, the longitudinal direction orientation becomes large, so that the orientation in the width direction becomes insufficient, and it may be easily broken when stretched in the width direction. On the other hand, when Δn is smaller than 0.01, the alignment in the longitudinal direction is insufficient and the alignment in the width direction may be excessive, which is not preferable. Moreover, it is preferable that the MOR-c value of a uniaxially stretched film is 1.0-1.8. More preferably, it is 1.05-1.5. When the MOR-c value is larger than 1.8, the alignment in the width direction may be insufficient, which is not preferable. When the MOR-c value is smaller than 1.05, the orientation in the longitudinal direction is insufficient, which is not preferable.

  A biaxially oriented film having an MOR-c value in a desired range can be obtained by stretching the uniaxially stretched film obtained under the above conditions in the width direction under the following conditions. The preheating temperature in the width direction stretching is preferably 70 to 100 ° C, more preferably 75 to 90 ° C. The stretching temperature in the width direction is preferably 80 ° C. or higher and 120 ° C. or lower, more preferably 80 ° C. or higher and 110 ° C. or lower, and most preferably 80 ° C. or higher and 95 ° C. or lower.

  It is preferable to heat-treat the film after biaxially stretching the unstretched sheet. This heat treatment can be performed by any conventionally known method such as in an oven or on a heated roll. The heat treatment can be performed at any film temperature of 120 ° C. or more and 245 ° C. or less, but preferably 221 to 245 ° C. More preferably, it is 225 degreeC-245 degreeC. The heat treatment time can be any time, but preferably 1 to 60 seconds. More preferably, it is 1 to 30 seconds. The heat treatment may be performed while relaxing the film in the longitudinal direction and / or the width direction. Furthermore, re-stretching may be performed once or more in each direction, and then heat treatment may be performed.

  The polyester film for molding of the present invention is a film containing polyester as a main component. That is, at least 50% by mass of the molding polyester film of the present invention is made of polyester.

  The polyester used in the molding polyester film of the present invention is a general term for polymers in which main bonds in the main chain are ester bonds, and is usually obtained by polycondensation reaction of a dicarboxylic acid component and a glycol component. be able to.

  Examples of the dicarboxylic acid component used here include terephthalic acid, isophthalic acid, phthalic acid, 2,6-naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenoxyethanedicarboxylic acid, and 5-sodiumsulfonedicarboxylic acid. Aromatic dicarboxylic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dimer acid, maleic acid, fumaric acid and other aliphatic dicarboxylic acids, 1,4-cyclohexanedicarboxylic acid and other alicyclic dicarboxylic acids, paraoxybenzoic acid Each component such as oxycarboxylic acid can be exemplified. Further, as dicarboxylic acid ester derivative components, esterified products of the above dicarboxylic acid compounds, such as dimethyl terephthalate, diethyl terephthalate, 2-hydroxyethyl methyl terephthalate, dimethyl 2,6-naphthalenedicarboxylate, dimethyl isophthalate, adipic acid Examples of the components include dimethyl, diethyl maleate, and dimethyl dimer. Among these, in the polyester in the entire polyester film for molding of the present invention, the proportion of terephthalic acid and / or naphthalenedicarboxylic acid is preferably 95 mol% or more, more preferably 98 mol% or more in the dicarboxylic acid component. Is preferable from the viewpoint of heat resistance and productivity.

  Examples of the glycol component include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexane. Diols, aliphatic dihydroxy compounds such as 2,2-dimethyl-1,3-propanediol (neopentyl glycol), polyoxyalkylene glycols such as diethylene glycol, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, 1,4-cyclohexane Examples thereof include alicyclic dihydroxy compounds such as dimethanol and spiroglycol, and aromatic dihydroxy compounds such as bisphenol A and bisphenol S. Among these, each component of ethylene glycol, 1,4-butanediol, 2,2-dimethyl-1,3-propanediol, and 1,4-cyclohexanedimethanol is preferably used in terms of moldability and handleability. Particularly, among glycol components, ethylene glycol is preferably 60 mol% or more from the viewpoint of heat resistance and productivity.

  Two or more of these dicarboxylic acid components and glycol components may be used in combination.

  From the viewpoint of moldability and dimensional stability, terephthalic acid is 95 mol% or more of the dicarboxylic acid component of the polyester constituting the molding polyester film, and ethylene glycol is 60 to 95 mol% of the glycol component, 1,4- It is preferable that the content of one or more glycol components selected from the group consisting of butanediol, 2,2-dimethyl-1,3-propanediol, or 1,4-cyclohexanedimethanol is 5 to 40 mol%. More preferably, ethylene glycol is 70 to 95 mol%, and at least one glycol component of 1,4-butanediol, 2,2-dimethyl-1,3-propanediol, or 1,4-cyclohexanedimethanol 5 to 30 mol%, more preferably 80 to 95 mol% of ethylene glycol, any one of 1,4-butanediol, 2,2-dimethyl-1,3-propanediol and 1,4-cyclohexanedimethanol One or more glycol components are 5 to 20 mol%.

  The molding polyester film of the present invention preferably has a three-layer constitution of B layer / A layer / B layer in order to achieve both moldability into a deep shape, high dimensional stability, and surface gloss. By making the surface layer and the center layer have different compositions in a three-layer structure, the conflicting requirements of moldability and dimensional stability can be satisfied.

  Further, 95 mol% or more of the dicarboxylic acid component of the polyester constituting the A layer is terephthalic acid, 60 to 95 mol% of the glycol component is ethylene glycol, 5 to 40 mol% is 1,4-cyclohexanedimethanol, 2 , 2-dimethyl-1,3-propanediol and 1,4-butanediol are one or more glycols, and 95% by mole or more of the dicarboxylic acid component of the polyester constituting the B layer is terephthalic Of the acid and glycol components, 80 mol% or more is ethylene glycol, 0 to 20 mol% is a group consisting of 1,4-cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol and 1,4-butanediol It is preferable that it is 1 or more types of glycol chosen from these.

  As for the dicarboxylic acid component of the polyester which comprises A layer, it is more preferable that terephthalic acid is 98 mol% or more, More preferably, it is 99 mol% or more. The glycol component of the polyester constituting the A layer is more preferably 80 mol% or more, more preferably 85 to 90 mol% of ethylene glycol, and 1,4-cyclohexanedimethanol, 2,2-dimethyl- The content of one or more glycols selected from the group consisting of 1,3-propanediol and 1,4-butanediol is more preferably 5 to 20 mol%, and even more preferably 10 to 15 mol%.

  As for the dicarboxylic acid component of the polyester which comprises B layer, it is more preferable that a terephthalic acid is 98 mol% or more, More preferably, it is 99 mol% or more. The glycol component of the polyester constituting the B layer is more preferably 90 to 99 mol%, more preferably 95 to 99 mol% of ethylene glycol, and 1,4-cyclohexanedimethanol, 2,2-dimethyl. The amount of one or more glycols selected from the group consisting of -1,3-propanediol and 1,4-butanediol is more preferably 0 to 10 mol%, still more preferably 1 to 5 mol%.

  Considering the interlayer adhesion between the A layer and the B layer, 99 mol% or more of the dicarboxylic acid component of the polyester constituting the A layer is terephthalic acid, and 85 to 90 mol% of the glycol component is ethylene glycol, 10 to 15 The mol% is 1,4-cyclohexanedimethanol and / or 2,2-dimethyl-1,3-propanediol, and 99 mol% or more of the dicarboxylic acid component of the polyester constituting the B layer is terephthalic acid, glycol component Of these, 95 to 99 mol% is most preferably ethylene glycol, and 1 to 5 mol% is most preferably 1,4-cyclohexanedimethanol and / or 2,2-dimethyl-1,3-propanediol.

  Among the glycol components of the A layer, by making the molar ratio of ethylene glycol 80 mol% or more, dimensional stability can be improved, wrinkles due to elongation during processing can be suppressed, and 1,4-cyclohexanedimethanol and / or Since moldability can be improved by making 2,2-dimethyl-1,3-propanediol 5 mol% or more, it is preferable. By making ethylene glycol 90 mol% or more of the glycol component of the B layer, good chemical resistance and heat resistance can be obtained, and 1,4-cyclohexanedimethanol and / or 2,2-dimethyl-1, By making 3-propanediol 10 mol% or less, the surface can be smoothed and high gloss is obtained, which is preferable.

  The thickness ratio of the A layer and the B layer is such that (B layer thickness) / (A layer thickness) / (B layer thickness) is in the range of 1/10/1 to 1/4/1. preferable. More preferably, it is the range of 1/9/1 to 1/7/1. Outside this range, it may be difficult to achieve both formability to a deep shape and dimensional stability, and uneven lamination may occur, which is not preferable. Said lamination thickness ratio can be achieved by adjusting the discharge amount when extruding the polyester A constituting the A layer and the polyester B constituting the B layer. The discharge amount can be appropriately adjusted depending on the number of rotations of the screw of the extruder, the number of rotations of the gear pump, the extrusion temperature, the viscosity of the polyester raw material, etc. when a gear pump is used.

  The film thickness ratio is determined by observing the cross section of the film with a scanning electron microscope, transmission electron microscope, optical microscope, etc. at a magnification of 500 to 10,000 times, and measuring the thickness of each layer. Can be requested.

  Further, in the polyester used for the molding polyester film of the present invention, so-called internal particles, inorganic particles and / or organic particles having an average particle diameter of 0.01 to 10 μm, which are precipitated due to a catalyst residue added during the polymerization reaction, etc. Particles arbitrarily selected from external particles such as particles can be contained. Here, if particles having an average particle diameter exceeding 10 μm are used, defects may occur in the film. Examples of the particles that can be used include inorganic particles such as wet and dry silica, colloidal silica, aluminum silicate, titanium oxide, calcium carbonate, calcium phosphate, barium sulfate, alumina, mica, kaolin, clay, and hydroxyapatite, and styrene, silicone, and acrylic acid. Organic particles having a component obtained by polymerizing methacrylic acid, ester, divinylbenzene or the like can be used. Of these, inorganic particles such as wet and dry silica and alumina, and organic particles composed of polymerized styrene, silicone, acrylic acid, methacrylic acid, ester, divinylbenzene and the like are preferably used. These internal particles, inorganic particles, and organic particles may be used in combination of two or more. Moreover, it is preferable that content in these films is the range of 0.01-5 mass% in total by making the whole polyester film for shaping | molding into 100 mass%. More preferably, it is 0.03 to 3 mass%. When the amount is less than 0.01% by mass, film winding may be difficult. When the amount exceeds 5% by mass, there is a possibility that glossiness decreases due to coarse protrusions, transparency and film-forming property deteriorate.

  In addition, in the case of a three-layer configuration of B layer / A layer / B layer, it is preferable from the viewpoint of achieving both winding property and economy that particles having an average particle diameter of 0.01 to 10 μm are added only to the B layer. . When adding particles only to the B layer, the particle concentration is preferably 0.01 to 5% by mass, more preferably 0.03 to 3% by mass, with the entire B layer being 100% by mass.

  In addition, as long as the effects of the present invention are not impaired, a polyfunctional compound such as trimellitic acid, trimesic acid, and trimethylolpropane can be copolymerized with the polyester used for the molding polyester film.

  Although it does not specifically limit as a catalyst at the time of manufacturing the polyester used for the polyester film for shaping | molding of this invention, An alkaline-earth metal compound, a manganese compound, a cobalt compound, an aluminum compound, an antimony compound, a titanium compound, a titanium / silicon composite An oxide, a germanium compound, or the like can be used. Of these, titanium compounds, titanium / silicon composite oxides, and germanium compounds are preferred from the viewpoint of catalytic activity.

  For example, when a titanium / silicon catalyst is added as a catalyst, a terephthalic acid component and an ethylene glycol component are reacted, then a titanium / silicon composite oxide and a phosphorus compound are added, and then a certain amount of diethylene glycol is contained under high temperature and reduced pressure. A method of obtaining a polyester by polycondensation reaction until the amount is obtained is preferably employed.

  Moreover, a phosphorus compound can be added as a heat stabilizer to the polyester film for molding of the present invention, and for example, phosphoric acid, phosphorous acid and the like are preferably used.

  In the molding polyester film of the present invention, additives such as a nucleating agent, an antistatic agent, a heat stabilizer, an antioxidant, a weathering agent, an ultraviolet absorber, a plasticizer, a pigment, and a dye do not impair the purpose of the present invention. Can be added in a range. The method for adding these additives is not particularly limited, and for example, they can be added during melt polymerization, solid phase polymerization, or extrusion molding of polyester.

  Next, a specific method for producing the molding polyester film of the present invention will be described.

  When the three-layer structure of B layer / A layer / B layer is used, each of the polyester A layer and the polyester B layer is weighed at a predetermined ratio and dried in a nitrogen atmosphere or a vacuum atmosphere before or after mixing. I do. It is preferable that the moisture content in the resin after drying is 50 ppm or less. Then, the mixed polyester resin is supplied to a known single or twin screw extruder and melt extruded. Next, foreign matter is removed and the amount of extrusion is leveled through a filter and a gear pump, respectively, and discharged from the T die onto a cooling drum in a sheet form. At that time, an electrostatic application method in which a cooling drum and the resin are brought into close contact with each other by static electricity using an electrode applied with a high voltage, a casting method in which a water film is provided between the casting drum and the extruded polymer sheet, The sheet-like polymer is brought into close contact with the casting drum, cooled and solidified by a method of sticking the extruded polymer at a glass transition point to (glass transition point−20 ° C.) or a combination of these methods, and unstretched. Get a film. Among these casting methods, when using polyester, a method of applying an electrostatic force is preferably used from the viewpoint of productivity and flatness.

  The molding polyester film of the present invention needs to have a MOR-c value of 1.81 to 8.0. In the case of the sequential biaxial stretching method, the film end portion is distorted by bowing, and the MOR-c value is higher than that of the central portion. In order to suppress distortion due to bowing, a cooling process having a certain length or more is provided between the transverse stretching and the heat treatment process within a range not impairing the gist of the present invention (Japanese Patent Laid-Open No. 3-193328). It is also possible to perform relaxation between them (Japanese Patent Publication No. 35-11774), or to provide a nip roll group (Japanese Patent Laid-Open No. 50-73978) between the transverse stretching and the heat treatment step. Boeing can also be suppressed by stretching with a tenter capable of simultaneous biaxial stretching (Japanese Patent Laid-Open No. 9-295345).

  Furthermore, in order to improve the adhesive strength with various processed layers such as printing layers, adhesives, vapor-deposited layers, hard coat layers, weathering layers, at least one side can be subjected to corona treatment or an easy-adhesion layer can be coated. . As a method of providing the coating layer in-line in the film manufacturing process, at least uniaxially stretched film with a coating layer composition dispersed in water is uniformly applied using a metalling bar or gravure roll. A method of drying the coating agent while stretching is preferable, and the thickness of the easy-adhesion layer is preferably 0.01 μm or more and 1 μm or less. When an easy adhesion layer is provided, various additives such as antioxidants, heat stabilizers, ultraviolet absorbers, infrared absorbers, pigments, dyes, organic or inorganic particles, antistatic agents, cores are provided in the easy adhesion layer. An agent or the like may be added. The resin preferably used for the easy-adhesion layer is preferably at least one resin selected from an acrylic resin, a polyester resin, and a urethane resin from the viewpoint of adhesiveness and handleability. An appropriate one is selected depending on the compatibility with the layer laminated on the easy-adhesion layer.

The polyester film for molding of the present invention has a thermal dimensional change rate of 180 ° C. in the orientation angle direction when the temperature is increased from 25 ° C. to 220 ° C. at a heating rate of 5 ° C./min with a load of 19.6 mN. 0 to + Ru 3% der. More preferably, it is 0 to + 2%. By setting the thermal dimensional change rate in the above range, it is possible to suppress distortion and deformation at the time of heating during processing and molding. If the thermal dimensional change rate is less than 0%, the film shrinks when held by a molding machine and is heated, and the molding stress increases, so that the moldability may deteriorate, which is not preferable. When the thermal dimensional change rate is larger than + 3%, it is not preferable because it may be wrinkled or misprinted when it is held in a molding machine and heated. The rate of thermal dimensional change is measured using a thermomechanical analysis (TMA) instrument. A sample with a width of 4 mm and a length of 15 mm was heated from 25 ° C. to 5 ° C./min under the condition of a load of 19.6 mN. Ask for.

  As a preferable means for setting the thermal dimensional change rate within the above range, an off-annealing treatment may be performed. By setting the off-annealing treatment temperature to 140 ° C. or more and 180 ° C. or less and lowering the winding speed by 0.5 to 5% from the unwinding speed, the thermal dimensional change rate can be within the range. Furthermore, it is preferable to provide a stepwise cooling zone after the off-annealing treatment because the rate of thermal dimensional change can be suppressed. The conditions for the off-annealing treatment are preferably adjusted by the orientation angle. For example, when the orientation angle is 0 to ± 45 °, the processing temperature is 150 to 180 ° C., the winding speed is reduced by 0.5 to 3% from the unwinding speed, and the orientation angle is ± 45 to ± 90 °. The treatment temperature is preferably 140 to 170 ° C., and the winding speed is preferably reduced by 1 to 5% from the unwinding speed. Further, the winding and winding positions may be shifted in parallel so that winding tension is applied along the orientation angle.

  The polyester film for molding of the present invention preferably has a thickness unevenness of 10% or less from the viewpoint of the appearance after molding. If the thickness unevenness is larger than 10%, the appearance of the molded product after molding transfer may be deteriorated. From the viewpoint of economy and appearance after molding, the thickness unevenness is more preferably 8% or less, and most preferably 5% or less. There are no particular limitations on the method of setting the thickness unevenness of the molding polyester film of the present invention to 10% or less. For example, the method of casting the casting position forward, the method of narrowing the lip gap of the die, the perfect circle of the cast drum or roll Examples thereof include a method of setting the degree (JIS B 0621-1984) to a certain value or less, a method of using a radiation heater in order to reduce stretching temperature unevenness, and the like.

  For example, when performing forward casting, it is preferable that the angle between the tangent line between the film and the cast drum is 30 ° or less at the contact point between the film and the cast drum. More preferably, it is 15 ° or less. If the angle between the film and the tangent is larger than 30 °, the adhesion between the film and the cast drum is deteriorated, which may cause uneven thickness.

  When the roundness is set to a certain value or less, the roundness is preferably 1% or less of the roll radius. More preferably, it is 0.5% or less. Higher accuracy is required for the roll in front of the process. In particular, in the case of a cast drum, 0.1% or less is preferable. The roundness of the cast drum or roll is expressed by the difference between the maximum radius and the minimum radius in the cross section. When the roundness is larger than 1% of the roll radius, the unevenness of the roll may be transferred to the film or the film feed speed may be uneven in the corresponding roll, which causes unevenness of thickness.

  When using a radiation heater at the time of extending | stretching, it is preferable to be used in extending | stretching of a longitudinal direction. A preferable output is 3 to 30 kW, more preferably 5 to 20 kW. If the output is insufficient, the amount of heat is insufficient, and if the output is excessive, thickness unevenness may be caused.

  The molding polyester film of the present invention is suitable for processing such as coating and printing because it has a low molding stress at high temperatures and can be molded into a deep shape and has a small dimensional change rate in the processing temperature region. Moreover, it can use suitably for decorating molding members, such as building materials, a motor vehicle part, and an electric appliance.

  Hereinafter, the present invention will be described in detail by way of examples. Various characteristics were measured and evaluated by the following methods.

1. MOR-c value, orientation angle Using MOA-2001 (frequency 4 GHz) manufactured by KS Systems (current Oji Scientific Instruments), the MOR value was measured, and the MOR-c value was calculated by the following equation (1). Asked.

MOR−c value = (MOR value−1) × tc / t + 1 (1)
Here, t is the thickness of the sample (μm), tc is the reference thickness to be corrected (188 μm), MOR is the ratio of the major axis to the minor axis of the polar coordinate (orientation pattern) obtained by the above measurement, MOR-c The value indicates the corrected MOR. The inclination in the orthogonal coordinate system of the major axis of polar coordinates is defined as the orientation angle.

2. F100 value at 150 ° C. in the direction perpendicular to the orientation angle, F100 value in the orientation angle direction A sample was cut into a width of 10 mm in the orientation angle obtained by measuring the MOR value and the direction perpendicular to the orientation angle. Using a tensile tester (Tensilon UCT-100 manufactured by Orientec Co., Ltd.), the cut sample is set so that the length between chucks is 50 mm (initial sample length), and the temperature is set to 150 ° C. and the humidity is set to 65% RH. After preheating for 60 seconds in the constant temperature layer, a tensile test was performed at a tensile speed of 300 mm / min, and the stress at 100% elongation was set to an F100 value. The number of measurements (hereinafter referred to as N) was N = 5.

3. Thermal dimensional change rate (180 ℃)
The film was cut into a rectangular shape having a length of 50 mm and a width of 4 mm in the orientation angle direction to obtain a sample. Using a thermomechanical analyzer (manufactured by Seiko Instruments, TMA EXSTAR 6000), the dimensional change rate of the film length when held under the following conditions was determined by N = 2.
Test length: 15mm
Load: 19.6mN
Temperature: 25 ° C to 220 ° C (5 ° C / min)
Thermal dimensional change rate (%) = [{film length at 180 ° C. (mm) −film length at 25 ° C. (mm)} / film length at 25 ° C. (mm)] × 100.

4). Thickness unevenness The film was cut into 10 cm × 10 cm, the thickness was measured at 5 points in the longitudinal direction, 5 points in the width direction, and 10 points in total, and the thickness unevenness was determined from the average value, maximum value, and minimum value.

5. Chemical resistance test The film was placed on a horizontal table, and each drop of toluene, ethyl acetate, and methyl ethyl ketone was dropped and wiped off after 10 seconds.

○: No traces left Δ: Traces (scratches) left after wiping off ×: Evaluation was made with three kinds of chemicals in which dripped traces remained, and Δ or more was regarded as acceptable for the worst results.

6). Printing processing test A film was cut out to 300 mm × 210 mm, and a lattice pattern was printed by a sheet-fed printing machine.

○: Printing was possible without any problem. Δ: The lattice pattern was slightly distorted. X: Wrinkles were found or the lattice pattern was shifted.

7). Molding test The molded sample was subjected to a molding test using a double-sided vacuum molding machine NGF-0406 (manufactured by Fuse Vacuum Co., Ltd.). The molding conditions were optimum conditions for each film between 150 ° C. and 190 ° C., and the mold was any one of (A) to (D).

(A) 60 mm x 150 mm x 30 mm squirrel type (semi-cylindrical type)
(B) A mold having a height of 20 mm embedded in clay from the bottom of the mold of (A) (C) A mold of 20 mm from the bottom of the mold in (A) embedded in clay and having a height of 10 mm (D) Box shape of 60 mm × 150 mm × 10 mm.

(1) Moldability ○: Molded Δ: Edge is slightly sweet, but molded ×: More than Δ which could not be molded sufficiently was regarded as acceptable.

(2) Dimensional stability ○: The lattice pattern was not abnormal. Δ: The lattice pattern was slightly distorted. X: The lattice pattern was largely distorted or broken.

(Polyester chip α)
To a mixture of 100 parts by weight of dimethyl terephthalate and 70 parts by weight of ethylene glycol, 0.09 parts by weight of magnesium acetate and 0.03 parts by weight of antimony trioxide are added, the temperature is gradually raised, and finally Conducted transesterification while distilling methanol at 220 ° C. Subsequently, 0.020 parts by mass of an aqueous solution of 85% by mass of phosphoric acid was added to the transesterification reaction product, and then transferred to a polycondensation reaction kettle. The reaction system is gradually depressurized while heating in the polymerization kettle, and the polycondensation reaction is performed at 290 ° C. under a reduced pressure of 1 hPa. The inherent viscosity is 0.65, and the by-produced diethylene glycol component is converted into the glycol component in the resin. On the other hand, a polyethylene terephthalate resin copolymerized with 2 mol% was obtained.

(Polyester chip β)
Copolyester in which 1,4-cyclohexanedimethanol component was copolymerized with 33 mol% with respect to the glycol component of polyethylene terephthalate was used.

(Polyester chip γ)
A copolymerized polyester in which the 2,2-dimethyl-1,3-propanediol component was copolymerized in an amount of 33 mol% with respect to the glycol component of polyethylene terephthalate was used.

(Polyester chip δ)
A polybutylene terephthalate resin (“Toraycon”, 1100S manufactured by Toray Industries, Inc.) chip was used.

(Particle Master M)
When the polyester chip α is produced, a polycondensation reaction is performed after adding an ethylene glycol slurry of aggregated silica particles having an average particle size of 2.2 μm after the transesterification reaction, and a particle master having a particle concentration of 2% by mass in the polymer is obtained. Produced.

Examples 1, 2, 3, 4, and 6 are read as Comparative Examples 5, 6, 7, 8, and 9, respectively.
Example 1
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip β and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours to sufficiently remove moisture, and then layer A has a mass ratio of polyester chip α: polyester chip β = 70: 30. The B layer is blended in a mass ratio of polyester chip α: polyester chip β: particle master M = 89: 10: 1 and fed to separate single screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film. Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, the preheating temperature was 90 ° C., the stretching temperature was 95 ° C., and the metal was stretched 3.3 times in the longitudinal direction and immediately temperature controlled to 40 ° C. Cooled with a roll. Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar. Next, the film was stretched 3.7 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter type horizontal stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a molding polyester film. A polyester film for molding printed with a sheet-fed printing press was molded with a mold (B). I was able to mold without problems.

(Comparative Example 1)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip β and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours to sufficiently remove moisture, and then layer A has a mass ratio of polyester chip α: polyester chip β = 70: 30. The B layer is blended in a mass ratio of polyester chip α: polyester chip β: particle master M = 89: 10: 1 and fed to separate single screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Then, before stretching in the longitudinal direction, the film temperature is raised with a heating roll, the preheating temperature is 75 ° C., the stretching temperature is 80 ° C., the stretching is performed 3.4 times in the longitudinal direction, and the temperature is immediately controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.4 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a biaxially oriented polyester film.
A biaxially oriented polyester film printed with a sheet-fed printing press was molded with a mold (B).
The side molding was inadequate, and even if the direction of the film was changed, it did not improve and became impossible.

(Example 2)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip γ and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours to sufficiently remove water, and then layer A has a mass ratio of polyester chip α: polyester chip γ = 80: 20 The B layer is blended at a mass ratio of polyester chip α: polyester chip γ: particle master M = 94: 5: 1, supplied to separate single-screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Next, before stretching in the longitudinal direction, the film temperature is raised with a heating roll, the preheating temperature is 80 ° C., the stretching temperature is 85 ° C., the stretching is 3.0 times in the longitudinal direction, and the temperature is immediately controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.7 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter type horizontal stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a molding polyester film.
A polyester film for molding printed with a sheet-fed printing press was molded with a mold (C).
I was able to mold without problems.

(Comparative Example 2)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip γ and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours to sufficiently remove water, and then layer A has a mass ratio of polyester chip α: polyester chip γ = 80: 20 The B layer is blended at a mass ratio of polyester chip α: polyester chip γ: particle master M = 94: 5: 1, supplied to separate single-screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Next, before stretching in the longitudinal direction, the film temperature is raised with a heating roll, the preheating temperature is 75 ° C., the stretching temperature is 80 ° C., the stretching is 2.5 times in the longitudinal direction, and the temperature is immediately controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 4.5 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter type horizontal stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a biaxially oriented polyester film.
A biaxially oriented polyester film printed with a sheet-fed printing press was molded with a mold (C).
Wrinkles occurred during printing, and the distortion after molding became impossible.

(Example 3)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
The polyester chip α, the polyester chip δ and the particle master M are each dried at 180 ° C. for 4 hours in a vacuum dryer to sufficiently remove moisture, and then the layer A has a mass ratio of polyester chip α: polyester chip δ = 70: 30. The B layer is blended in a mass ratio of polyester chip α: polyester chip δ: particle master M = 94: 5: 1, and supplied to each single screw extruder, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, the preheating temperature was 80 ° C., the stretching temperature was 85 ° C., and the film was stretched 3.3 times in the longitudinal direction and immediately temperature controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.5 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a molding polyester film.
A polyester film for molding printed with a sheet-fed printing press was molded with a mold (B).
I was able to mold without problems. The chemical resistance test was no problem.

(Comparative Example 3)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
The polyester chip α, the polyester chip δ and the particle master M are each dried at 180 ° C. for 4 hours in a vacuum dryer to sufficiently remove moisture, and then the layer A has a mass ratio of polyester chip α: polyester chip δ = 70: 30. The B layer is blended in a mass ratio of polyester chip α: polyester chip δ: particle master M = 94: 5: 1, and supplied to each single screw extruder, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
An unstretched polyester film for molding printed by a sheet-fed printing press was molded with a mold (B).
There was no problem with molding, but in the chemical resistance test, traces of dripping with toluene, ethyl acetate, and methyl ethyl ketone remained.

Example 4
It was set as the film of single layer structure.
Polyester chip α, polyester chip β and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours to sufficiently remove moisture, and then polyester chip α: polyester chip β: particle master M = 79: 20: 1 The mixture was fed to a single screw extruder, melted at 275 ° C., passed through a filter, removed foreign matter, and the amount of extrusion was leveled. The sheet was discharged onto the sheet. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Next, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, the preheat temperature was 80 ° C., the stretching temperature was 90 ° C., and the metal was stretched 3.3 times in the longitudinal direction and immediately controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.5 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a molding polyester film.
A polyester film for molding printed with a sheet-fed printing press was molded with a mold (D).
I was able to mold without problems.

(Comparative Example 4)
It was set as the film of single layer structure.
The polyester chip α and the particle master M are each dried at 180 ° C. for 4 hours in a vacuum dryer to sufficiently remove water, and then blended at a mass ratio of polyester chip α: particle master M = 99: 1 and uniaxial extrusion. It was supplied to a machine, melted at 275 ° C., passed through a filter, removed foreign matter, and the amount of extrusion was leveled, and then discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Then, before stretching in the longitudinal direction, the film temperature is raised with a heating roll, the preheating temperature is 100 ° C., the stretching temperature is 110 ° C., the stretching is 3.3 times in the longitudinal direction, and the temperature is immediately controlled to 40 ° C. Cooled with a roll.
Next, the film was stretched 3.5 times in the width direction at a preheating temperature of 90 ° C. and a stretching temperature of 100 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a biaxially oriented polyester film.
A biaxially oriented polyester film printed with a sheet-fed printing press was molded with a mold (D).
It was not able to mold enough.

(Example 5)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip β and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours, and after sufficiently removing water, layer A has a mass ratio of polyester chip α: polyester chip β = 60: 40 The B layer is blended in a mass ratio of polyester chip α: polyester chip β: particle master M = 89: 10: 1 and fed to separate single screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Then, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, the preheat temperature was 85 ° C., the stretching temperature was 95 ° C., and the metal was stretched 3.3 times in the longitudinal direction and immediately temperature controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.5 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a biaxially oriented polyester film.
The biaxially oriented polyester film was subjected to an off-annealing treatment in a hot air oven at 150 ° C. while reducing the longitudinal winding speed by 1.5% from the unwinding speed to obtain a molding polyester film.
A polyester film for molding printed with a sheet-fed printing press was molded with a mold (A).
Molding was possible without problems, and the grid pattern after molding was not distorted.

(Example 6)
It was set as the 3 layer laminated film of B layer / A layer / B layer.
Polyester chip α, polyester chip β and particle master M are each dried in a vacuum dryer at 180 ° C. for 4 hours, and after sufficiently removing water, layer A has a mass ratio of polyester chip α: polyester chip β = 60: 40 The B layer is blended in a mass ratio of polyester chip α: polyester chip β: particle master M = 89: 10: 1 and fed to separate single screw extruders, melted at 275 ° C., and separately. After removing the foreign matter and leveling the amount of extrusion through the filter and gear pump, the B / A / B thickness ratio is 1/8 in the feed block installed on the top of the T-die. After being laminated so as to be / 1, the sheet was discharged from a T-die onto a cooling drum whose temperature was controlled at 25 ° C. At that time, a wire-like electrode having a diameter of 0.1 mm was applied electrostatically and adhered to the cooling drum to obtain an unstretched film.
Then, before stretching in the longitudinal direction, the film temperature was raised with a heating roll, the preheat temperature was 85 ° C., the stretching temperature was 95 ° C., and the metal was stretched 3.3 times in the longitudinal direction and immediately temperature controlled to 40 ° C. Cooled with a roll.
Thereafter, corona discharge treatment was performed, and an easy-adhesion layer mainly composed of a water-dispersed acrylic resin was applied with a metalling bar.
Next, the film was stretched 3.5 times in the width direction at a preheating temperature of 80 ° C. and a stretching temperature of 90 ° C. with a tenter-type transverse stretching machine, and the temperature was maintained at 230 ° C. for 5 seconds while relaxing 4% in the width direction. Heat treatment was performed to obtain a molding polyester film.
A polyester film for molding printed with a sheet-fed printing press was molded with a mold (A).
Slightly sweet edges could be molded, and the lattice pattern after molding was slightly distorted, but there was no problem.

  The molding polyester film of the present invention has a suitable orientation bias and low stress, and has both moldability and dimensional stability, and has excellent processability. Therefore, it is decorated by coating, laminating, printing, vapor deposition, etc. be able to. For example, it can be suitably used for decorating molded members such as building materials, mobile devices, electrical products, automobile parts, and gaming machine parts.

Claims (4)

A MOR-c values from 1.81 to 8.0, Ri 60MPa der less F100 value is 5MPa or more at 0.99 ° C. in the orthogonal direction of the orientation angle, a load 19.6 mN, raised to 220 ° C. from 25 ° C. rise rate 5 ° C. / min for polyester molding thermal dimensional change of from 0 + Ru 3% der of the film at 180 ° C. in the orientation angle direction when the temperature is raised in the film. The polyester film for molding according to claim 1 , comprising a three-layer constitution of B layer / A layer / B layer. Of the dicarboxylic acid component of the polyester constituting the A layer, 95 mol% or more is terephthalic acid, of the glycol component, 60 to 95 mol% is ethylene glycol, 5 to 40 mol% is 1,4-cyclohexanedimethanol, 2,2 -One or more glycol selected from the group consisting of dimethyl-1,3-propanediol and 1,4-butanediol, and 95 mol% or more of the dicarboxylic acid component of the polyester constituting the B layer is terephthalic acid, glycol Of the components, 80 mol% or more is selected from the group consisting of ethylene glycol, 0 to 20 mol% is 1,4-cyclohexanedimethanol, 2,2-dimethyl-1,3-propanediol and 1,4-butanediol. The polyester film for molding according to claim 2 , which is one or more glycols. 95 mol% or more of the dicarboxylic acid component of the polyester constituting the A layer is terephthalic acid, 80 to 95 mol% of the glycol component is ethylene glycol, 5 to 20 mol% is 1,4-cyclohexanedimethanol and / or 2 , 2-dimethyl-1,3-propanediol, 95 mol% or more of the dicarboxylic acid component of the polyester constituting the B layer is terephthalic acid, 90 mol% or more of the glycol component is ethylene glycol, 0 to 10 mol The molding polyester film according to claim 2 , wherein% is 1,4-cyclohexanedimethanol and / or 2,2-dimethyl-1,3-propanediol.